truck pumps should not used to fuel cars, their flow rate is way to high and will cause damage if not bathe you in fuel. I haven't ever had an issue find low sulfur diesel on my travels, however I am mostly doing than East of the Mississippi.
Right about the truck pumps - I guess the main thing is that because trucks and other large diesel fuel consumers exist and are popular, the overall infrastructure for diesel, including refining and distribution networks, also exist. An individual pump is only a small part of that network.
